A wet desulfurization water-saving intelligent regulation control system and method

Abstract

The present invention proposes a wet flue gas desulfurization water-saving intelligent regulation control system and method, the control system comprises a wet flue gas desulfurization tower and a flue condenser connected in sequence through a flue gas pipeline, comprises a condensate buffer water tank connected to the bottom of the flue condenser through a condensate pipeline, and also comprises an electric valve, a flow meter, a SO2 detector, a humidity detector, a first thermometer, a second thermometer, and a third thermometer interconnected with a water balance intelligent controller through a signal transmission channel. The present invention realizes the determination and intelligent regulation of the water consumption q1 of the wet flue gas desulfurization tower and the water collection q2 of the flue condenser through efficient coupling of the flue condenser and the wet flue gas desulfurization tower water system, which not only reduces the water consumption of the wet flue gas desulfurization system, but also realizes the self-regulation of the water balance of the wet flue gas desulfurization system and the zero water replenishment of the system according to different needs.

Description

[Technical field]

[0001] The invention relates to the technical field of industrial flue gas desulfurization and purification, and in particular to a wet flue gas desulfurization water-saving intelligent regulation control system and method. [Background technology]

[0002] In many fields such as coal-fired power plants, coking, sintering, and waste incineration, as the country's air pollutant emission standards become increasingly stringent, ultra-low emission equipment for desulfurization and denitrification has basically become an environmental protection standard. Wet desulfurization is the most mainstream flue gas desulfurization technology. While achieving efficient desulfurization, it also has the risk of water balance imbalance and high water consumption.

[0003] At present, the wet flue gas desulfurization system should adopt or develop a variety of mature technologies to control the risk of water balance imbalance: for example, invention patent authorization number CN107224865B proposes to use a water collection tank arranged under the demister to collect defogger flushing water, and use bypass technology to realize the flushing water directly returning to the desulfurization tower or entering the water collection tank for recycling, so as to maintain the water balance of the system; invention patent application number 201510071613.9 proposes to transport the filtered water in the flushing filter pool to the slurry tank for full or partial replacement of pulping water, so as to achieve water system rebalancing; invention patent application number 201711400205.9 proposes a control method for improving the dynamic characteristics of water balance of a series tower desulfurization system, so as to realize dynamic control of water balance between the primary and secondary towers.

[0004] Since 2017, with the rise of the colored plume management market, flue condensation water collection technology has been widely used, and the high water consumption problem of wet flue gas desulfurization system has been effectively alleviated, but the selection and effective control of condensate water reuse methods that followed have not received due attention. Therefore, the applicant is committed to developing a wet flue gas desulfurization water-saving intelligent regulation control system and method to achieve self-regulation and zero water replenishment of the water balance of the wet flue gas desulfurization system. [Summary of the invention]

[0005] The purpose of the present invention is to solve the problems in the prior art and to propose a wet flue gas desulfurization water-saving intelligent regulation control system and method. By recovering the water content of the flue gas at the outlet of the wet flue gas desulfurization tower as recycled water for the water system, it can not only save water but also achieve the purpose of intelligent regulation.

[0006] To achieve the above-mentioned purpose, the present invention proposes a wet flue gas desulfurization water-saving intelligent regulation and control system, comprising a wet flue gas desulfurization tower, a flue condenser, a water balance intelligent controller, an electric valve, a condensate buffer water tank, a flow meter, a SO2 detector, a humidity detector, a first thermometer, a second thermometer, and a third thermometer. The inlet flue of the wet flue gas desulfurization tower is provided with a flow meter, a SO2 detector, a humidity detector and a first thermometer. The outlet flue of the wet flue gas desulfurization tower is connected to the inlet flue of the flue condenser. The condensate pipe at the bottom of the flue condenser is connected to the condensate buffer water tank. A second thermometer is also provided on the outlet flue of the desulfurization tower, and a third thermometer is also provided on the outlet flue of the flue condenser. The flow meter, SO2 detector, humidity detector, first thermometer, second thermometer and third thermometer are electrically connected to the water balance intelligent controller through a signal transmission channel, and the detected flue gas parameters are transmitted to the water balance intelligent controller. The water balance intelligent controller is electrically connected to the electric valve through the signal transmission channel to control the opening of the electric valve. The inlet of the electric valve is connected to the cold source, and the outlet of the electric valve is connected to the flue condenser.

[0007] Preferably, the flow meter, SO2 detector, humidity detector and first thermometer are sequentially arranged on the inlet flue of the wet flue gas desulfurization tower along the flue gas input direction; the flow meter is used to detect the raw flue gas flow rate, the SO2 detector is used to detect the SO2 content of the raw flue gas, the humidity detector is used to detect the water content of the raw flue gas, and the first thermometer is used to detect the raw flue gas temperature.

[0008] Preferably, the second thermometer is used to detect the temperature of the clean flue gas after desulfurization.

[0009] Preferably, the third thermometer is used to detect the temperature of the net flue gas after condensation and water collection.

[0010] The present invention also proposes a control method for a wet desulfurization water-saving intelligent regulation control system, which comprises the following steps in sequence:

[0011] S1. The original flue gas before desulfurization passes through the wet desulfurization tower and flue condenser in sequence, and after desulfurization and condensation and water collection operations, it is transported to the chimney for discharge;

[0012] S2. The flow rate Q, SO2 content Φ1, water content Φ2, temperature T1 of the original flue gas, and the temperature T2 of the clean flue gas after desulfurization are respectively transmitted to the water balance intelligent controller through the flow meter, SO2 detector, humidity detector, first thermometer and second thermometer. The water balance intelligent controller automatically calculates the water consumption q1 of the wet desulfurization tower according to the received signal;

[0013] S3. The third thermometer transmits the temperature T3 of the clean flue gas after condensate collection and water recovery detected to the water balance intelligent controller, and the water balance intelligent controller automatically calculates the water recovery quantity q2 of the flue gas condenser according to Q, T2, and T3;

[0014] S4. The water balance intelligent controller makes a judgment and automatic adjustment on the obtained water consumption quantity q1 and water recovery quantity q2;

[0015] S5. The condensate collection water of the flue gas condenser enters the condensate water buffer tank through the condensate water pipeline, and then realizes the self-adjustment of the water balance of the wet desulfurization system and zero water replenishment according to different requirements.

[0016] Preferably, the judgment basis for implementing step S4 is: if q1>q2, the water balance intelligent controller outputs a signal to control the electric valve to increase the opening degree, reduce the temperature T3 of the clean flue gas at the outlet of the flue gas condenser, and thus increase q2; if q1<q2, the water balance intelligent controller outputs a signal to control the electric valve to reduce the opening degree, increase the temperature T3 of the clean flue gas at the outlet of the flue gas condenser, and thus reduce q2.

[0017] Preferably, the judgment condition for the end of step S4 is 99%≤q2 / q1≤101%.

[0018] Preferably, in step S5, according to different requirements, the water outlet of the condensate water buffer tank is used as the flushing water for the desulfurization demister or the pulping water.

[0019] The beneficial effects of the present invention:

[0020] 1. The present invention adopts the flue gas condensation technology to achieve the efficient recovery of the water content in the flue gas at the outlet of the wet desulfurization tower, realizing energy conservation and water conservation.

[0021] 2. The present invention completes the efficient coupling of the flue gas condenser and the water system of the wet desulfurization tower through the intelligent adjustment control system, realizing the self-adjustment of the water balance of the wet desulfurization tower and zero water replenishment.

[0022] The features and advantages of the present invention will be described in detail through embodiments in conjunction with the drawings.

Description of the Drawings

[0023] Figure 1 It is the structure diagram of an intelligent adjustment control system for water conservation in wet desulfurization of the present invention.

[0024] In the figure: 1 - wet desulfurization tower, 2 - flue gas condenser, 3 - water balance intelligent controller, 4 - electric valve, 5 - condensate water buffer tank, 6 - flowmeter, 7 - SO2 detector, 8 - humidity detector, 91 - first thermometer, 92 - second thermometer, 93 - third thermometer.

Specific Embodiments

[0025] See also Figure 1 The present invention provides a wet flue gas desulfurization water-saving intelligent regulating and controlling system, which includes a wet flue gas desulfurization tower 1, a flue gas condenser 2, a water balance intelligent controller 3, an electric valve 4, a condensate buffer water tank 5, a flow meter 6, a SO2 detector 7, a humidity detector 8, a first thermometer 91, a second thermometer 92, and a third thermometer 93. The inlet flue gas of the wet flue gas desulfurization tower 1 is provided with a flow meter 6, a SO2 detector 7, a humidity detector 8 and a first thermometer 91. The outlet flue gas of the wet flue gas desulfurization tower 1 is connected to the inlet flue gas of the flue gas condenser 2. The condensate water pipe at the bottom of the flue gas condenser 2 is connected to the condensate buffer water tank 5. The wet flue gas desulfurization tower 1 is connected to the inlet flue gas of the flue gas condenser 2. The condensate water pipe at the bottom of the flue gas condenser 2 is connected to the condensate buffer water tank 5. A second thermometer 92 is also provided on the outlet flue, and a third thermometer 93 is also provided on the outlet flue of the flue condenser 2. The flow meter 6, SO2 detector 7, humidity detector 8, first thermometer 91, second thermometer 92, and third thermometer 93 are respectively electrically connected to the water balance intelligent controller 3 through a signal transmission channel, and the detected flue gas parameters are transmitted to the water balance intelligent controller 3. The water balance intelligent controller 3 is electrically connected to the electric valve 4 through the signal transmission channel to control the opening of the electric valve 4. The inlet of the electric valve 4 is connected to the cold source, and the outlet of the electric valve 4 is connected to the flue condenser 2.

[0026] Furthermore, the flow meter 6, SO2 detector 7, humidity detector 8 and first thermometer 91 are sequentially arranged on the inlet flue of the wet flue gas desulfurization tower 1 along the flue gas input direction, the flow meter 6 is used to detect the original flue gas flow, the SO2 detector 7 is used to detect the SO2 content of the original flue gas, the humidity detector 8 is used to detect the water content of the original flue gas, and the first thermometer 91 is used to detect the original flue gas temperature. The second thermometer 92 is used to detect the temperature of the clean flue gas after desulfurization. The third thermometer 93 is used to detect the temperature of the clean flue gas after condensation and water collection.

[0027] Example 1

[0028] A control method for a wet desulfurization water-saving intelligent regulation control system comprises the following steps:

[0029] S1. Before desulfurization, the original flue gas first passes through the wet desulfurization tower 1 for desulfurization operation, the temperature is reduced by about 50°C, and then passes through the flue condenser 2 for condensation and water collection operation, the temperature drops to 42-48°C, and then is transported to the chimney for discharge;

[0030] S2. The detected raw flue gas flow rate Q, SO2 content Φ1, water content Φ2, temperature T1 of the raw flue gas, and temperature T2 of the clean flue gas after desulfurization are respectively transmitted to the water balance intelligent controller 3 through the flow meter 6, SO2 detector 7, humidity detector 8, first thermometer 91, and the second thermometer 92. The water balance intelligent controller 3 automatically calculates the water consumption q1 of the wet desulfurization tower 1 based on the above signals;

[0031] S3. The temperature T3 of the clean flue gas after condensation water collection detected by the third thermometer 93 is transmitted to the water balance intelligent controller 3. The water balance intelligent controller 3 automatically calculates the water collection amount q2 of the flue gas condenser 2 based on Q, T2, and T3;

[0032] S4. The water balance intelligent controller 3 makes a determination and automatic adjustment of the obtained q1 and q2;

[0033] If q1 > q2, the water balance intelligent controller 3 outputs a signal to increase the opening degree of the electric valve 4, reduce the temperature T3 of the clean flue gas at the outlet of the flue gas condenser 2, and thus increase q2;

[0034] If q1 < q2, the water balance intelligent controller 3 outputs a signal to reduce the opening degree of the electric valve 4, increase the temperature T3 of the clean flue gas at the outlet of the flue gas condenser 2, and thus reduce q2;

[0035] When 99% ≤ q2 / q1 ≤ 101% is satisfied, the determination ends.

[0036] S5. The condensed water collected by the flue gas condenser 2 enters the condensed water buffer tank 5 through the condensed water pipeline, and then realizes the self - adjustment of the water balance of the wet desulfurization system and zero water make - up according to different requirements. That is, according to different requirements, the water output from the condensed water buffer tank 5 can be used as the flushing water for the desulfurization demister or the pulping water.

[0037] The above embodiments are illustrative of the present invention, not limiting of the present invention. Any scheme obtained by simply transforming the present invention belongs to the protection scope of the present invention.

Claims

1. A control method for a wet flue gas desulfurization water-saving intelligent regulation and control system, characterized in that: A wet flue gas desulfurization water-saving intelligent regulating and controlling system is used, the wet flue gas desulfurization water-saving intelligent regulating and controlling system comprising a wet flue gas desulfurization tower (1), a flue gas condenser (2), a water balance intelligent controller (3), an electric valve (4), a condensate buffer water tank (5), a flow meter (6), an SO2 detector (7), a humidity detector (8), a first thermometer (91), a second thermometer (92), and a third thermometer (93). The inlet flue gas of the wet flue gas desulfurization tower (1) is provided with a flow meter (6), an SO2 detector (7), a humidity detector (8), and a first thermometer (91). The outlet flue gas of the wet flue gas desulfurization tower (1) is connected to the inlet flue gas of the flue gas condenser (2). The condensate water pipeline at the bottom of the flue gas condenser (2) is connected to the condensate buffer water tank (5). Then, the outlet flue of the wet desulfurization tower (1) is also provided with a second thermometer (92), the outlet flue of the flue condenser (2) is also provided with a third thermometer (93), the flow meter (6), the SO2 detector (7), the humidity detector (8), the first thermometer (91), the second thermometer (92), and the third thermometer (93) are respectively electrically connected to the water balance intelligent controller (3) through a signal transmission channel, and the detected flue gas parameters are transmitted to the water balance intelligent controller (3), the water balance intelligent controller (3) is electrically connected to the electric valve (4) through the signal transmission channel, and is used to control the opening of the electric valve (4), the inlet of the electric valve (4) is connected to the cold source, and the outlet of the electric valve (4) is connected to the flue condenser (2); The flow meter (6), the SO2 detector (7), the humidity detector (8) and the first thermometer (91) are arranged in sequence on the inlet flue of the wet flue gas desulfurization tower (1) along the flue gas input direction; the flow meter (6) is used to detect the flow rate of the original flue gas, the SO2 detector (7) is used to detect the SO2 content of the original flue gas, the humidity detector (8) is used to detect the water content of the original flue gas, and the first thermometer (91) is used to detect the temperature of the original flue gas; The second thermometer (92) is used to detect the temperature of the clean flue gas after desulfurization; The control method comprises the following steps in sequence: S1. The original flue gas before desulfurization passes through the wet desulfurization tower (1) and the flue condenser (2) in sequence, undergoes desulfurization and condensation and water collection operations, and is then transported to the chimney for discharge; S2. The flow rate Q, SO2 content Φ1, water content Φ2, temperature T1 of the original flue gas, and temperature T2 of the clean flue gas after desulfurization detected are respectively transmitted to the water balance intelligent controller (3) through the flow meter (6), the SO2 detector (7), the humidity detector (8), the first thermometer (91), and the second thermometer (92), and the water balance intelligent controller (3) automatically calculates the water consumption q1 of the wet desulfurization tower (1) according to the received signals; S3. The third thermometer (93) transmits the detected temperature T3 of the clean flue gas after condensation water collection to the water balance intelligent controller (3), and the water balance intelligent controller (3) automatically calculates the water collection amount q2 of the flue gas condenser (2) according to Q, T2, and T3; S4. The water balance intelligent controller (3) makes a determination and automatic adjustment of the obtained water consumption q1 and water collection amount q2; S5. The condensed water collected by the flue gas condenser (2) enters the condensed water buffer tank (5) through the condensed water pipeline, and then realizes the self-adjustment of the water balance of the wet flue gas desulfurization system and zero water make-up of the system according to different requirements; The determination basis for implementing step S4 is: a. If q1 > q2, the water balance intelligent controller (3) outputs a signal to control the electric valve (4) to increase the opening degree, reduce the temperature T3 of the clean flue gas at the outlet of the flue gas condenser (2), and thereby increase q2; b. If q1 < q2, the water balance intelligent controller (3) outputs a signal to control the electric valve (4) to reduce the opening degree, increase the temperature T3 of the clean flue gas at the outlet of the flue gas condenser (2), and thereby reduce q2.

2. The control method of a wet flue gas desulfurization water-saving intelligent regulation and control system according to claim 1, characterized in that: The determination condition for the end of step S4 is 99% ≤ q2 / q1 ≤ 101%.

3. The control method of a wet flue gas desulfurization water-saving intelligent regulation and control system according to claim 1, characterized in that: In step S5, according to different requirements, the water output from the condensed water buffer tank (5) is used as the flue gas desulfurization demister flushing water or the pulping water.

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